Posted by alexandra_k on August 17, 2005, at 2:47:37
In reply to on the absurdity of paving the roads with water, posted by alexandra_k on August 16, 2005, at 19:48:05
Though I'm fairly dodgey on this stuff really...
I'm missing something.
By observable, qualitative, superficial etc properties they mean at a casual glance. H2O and XYZ might appear similar in the way that H2O and gin can appear similar. Jackson didn't want to commit himself to qualitatively *identical* under scientific observations.
Though he said that scientists think that while this world is made of matter, it is possible that there be a world qualitatively identical to ours that is made of anti-matter. Where the particles circle the nucleas in the opposite direction or something...
If that is possible then you would have two qualitatively identical worlds that differed with respect to essential properties: one is made of matter and the other is made of anti-matter.
Maybe qualitative similarities are multiply realised at a lower level of analysis.
I think it might be that that they are attempting to capture.
And that we defer to a lower level of analysis.
But... Thats not all that interests us. For a while meaning2 fell in disrepute. Philosophers turned from the messy and tricky study of meanings to the less messy and tricky study of extensions / referents. They went so far as to dub extensions / referents meanings.
Content externalism is the view that mental content (ideas, thoughts, the reference / meaning of words) is outside the head. It is in the object / set of objects that the speaker has come into causal contact with.
Hillary Putnam considered whether the proposition 'I am a brain in a vat' is meaningful...
He considers that if I am a brain in a vat of nutrients being stimulated in certain ways by mad scientists (and have been all my life) then I cannot think about vats because I have not come into causal contact with vats. In fact I have not come into causal contact with brains either, so I am unable to think about brains and vats.
In English the word 'vat' refers to vats in the world. In vat English, however, the word 'vat' would refer to something along the lines of 'neural stimulation x'. The referents are different in english and vat english and thus the terms do not refer to / mean the same thing.
Thus it follows like this...
(P1) If I was a brain in a vat then I would not be able to think the thought 'I am a brain in a vat'.
(P2) But clearly I can think the thought 'I am a brain in a vat'.
_________________________________________________
(C) Therefore I know that I am not a brain in a vat.HA!
Howz that for an attempted defeat of radical sceptisism (which is the view that you cannot know whether you are or are not a brain in a vat).
Basically it falls down insofar as we don't know whether we can think 'I am a brain in a vat' because we don't know whether we have come into causal contact with brains and vats or not.
(P2) and (C) have the same truth values. The trouble is that we can't assume the truth of one to prove the truth of the other.
This argument is called a transcendental argument. I'm starting to wonder whether that means that when you accept the argument that is because you have seen how to transcend the problem. The trouble with the formal structure of transcendental arguments is that they are circular. They assume something that they need to prove. (P2) is reason to believe (C) but then (C) is the reason to believe (P2).
The ontological argument for the existence of god functions like this (IMO)
These are both facts that go beyond how things qualitatively seem to be to us. Qualitatively there is no difference between thinking english and thinking vat english thoughts.
Instead of alleviating scepticism about knowledge of the external world
Scepticism infects knowledge of the contents of ones mind...We cannot determine the content of our thoughts / words from how they seem to us.
Appearances can be misleading...
Is the moral of content externalism.
(What this does is carve the nasty, messy topic of meaning up. Reference gets to pick up one hell of a lot. If meaning = reference then we don't know what we mean much of the time...)
'Radical translation begins at home'
Quine
poster:alexandra_k
thread:541758
URL: http://www.dr-bob.org/babble/write/20050807/msgs/542813.html